Aug 29 (Reuters) - Canada’s main stock index was set to open lower on Tuesday as investors turned cautious after North Korea fired a missile over Japan’s northern Hokkaido island, sparking concerns of fresh tension between Washington and Pyongyang.

A decline in oil prices also weighed on index futures as markets grappled with the damage caused by hurricane Harvey.

September futures on the S&P TSX index were down 0.66 percent at 7:15 a.m. ET.

Canada producer prices data for July is due at 8:30 a.m. ET .

Canada’s main stock index was little changed on Monday as a decline in U.S. crude oil prices weighed on shares of energy companies, offsetting a gain in the gold-mining sector.

Dow Jones Industrial Average e-mini futures were down 0.43 percent at 7:15 a.m. ET, while S&P 500 e-mini futures were down 0.53 percent and Nasdaq 100 e-mini futures were down 0.77 percent.